fix for djangorestframework>3.3.2
fix for djangorestframework>3.3.2

vlfedotov/django-business-logic,vlfedotov/django-business-logic,vlfedotov/django-business-logic,dgk/django-business-logic,dgk/django-business-logic,dgk/django-business-logic,dgk/django-business-logic,vlfedotov/django-business-logic,vlfedotov/django-business-logic,dgk/django-business-logic